Closed captioning of: Save the date! Royal wedding details revealed

>>and i'm
matt lauer
. and take a look live at
westminster abbey
. we understand the queen is there this morning and we now know that
prince william
and
kate middleton
, now known as katharine middleton. if you had planned for
april 29
, cancel them. that's 157 days from now. we'll start to put a little counter up on the bottom of the screen there from now on.

>>the announcement was made at st. james palace shortly before we went on the air this morning and now there are just a new additional details to be sorted out like the guest list, the reception and, yes,
kate
's
wedding dress
. which designer will she choose? what is it going to look like? and how much will it cost? we'll get some insight from the one who designed
princess diana
's gown.

>> reporter: looks like we have a spring wedding here at
westminster abbey
. this is a 1,000-year-old church. it is rich in royal history. there have been royal burials, coronations and of course weddings and
prince william
will be the latest wedding. this seems to be something of a victory for the prince. he had been pushing for a spring date. we could be in trouble here with rain. we see some issues on this issue, it seems
prince william
got it right. the ceremony will be
broadcast live
around the world with 1 billion people watching, the kind of attention a future
british king
can expect, but the average girl growing up expecting a smaller event. here she is in a
school day
.

>>i wish to marry you.

>>be careful what you wish for young
kate
. a royal engagement can also be a
rude awakening
.
kate
like diana in the '80s is under a microscope.

>>the palace are very aware that she's going to be taking on the biggest role in her life and they're paving the way for there to be a support network for her.

>>the queen is very much of
kate
's and there's a feeling that could really help guide indicate into the role.

>> reporter: lack of privacy, an endless series of rigid protocols,
kate middleton
's new reality. her friends and family say she's up for it. a strength she often showed as an athlete.

>>kate
is a very intelligent
human being
and she'll handle it.

>> reporter: having watched his mother diana struggle, william is said to be very aware of how difficult this life will be for
kate
. it's a high price to pay for
falling in love
with a prince. you're looking at a
live shot
of
westminster abbey
. appropriately enough, she was married in
westminster abbey
and now we know that her grandson will be married there as well.

The announcement, made at St. James's Palace, came a week after the pair made news of their engagement public, also via an official statement from St. James's Palace.

Prince William's private secretary, Jamie Lowther-Pinkerton, said the couple chose the 1,000-year-old abbey in central London because despite its size — it holds 2,200 people — it has a sense of intimacy.

"Even at the altar, it seems like a parish church," he said.

William and Kate decided against celebrating their nuptials at St. Paul's Cathedral, where William's parents married in 1981.

Who's payingRetail researchers have estimated that the wedding could give a $1 billion boost to the British economy, but Lowther-Pinkerton said the couple were very mindful of the austere times facing many Britons following the coalition government's announcement of massive spending cuts.

"To that end the royal family and the Middleton family will pay for the wedding."

A royal aide said that meant the royal family and the Middletons would pay for the ceremony, reception and the honeymoon, while other costs, such as the bill for security, would be met by the taxpayer.

The royal aide said the couple, both 28, had always wanted a spring wedding and for it to be held on a Friday.

"Prince William has won his first battle, he wanted a wedding sooner rather than later and that’s what he’s got," said royal correspondent for Britain's News of the World newspaper Robert Jobson to NBC's TODAY.

Lowther-Pinkerton also said the guest list had not been finalized, but that "we will have a full church."

He said William and Kate were playing "a very active role" in planning the day.

"We know that the world will be watching on the 29th of April, and the couple are very, very keen indeed that the spectacle should be a classic example of what Britain does best," he said.

"The couple are completely over the moon," Lowther-Pinkerton added. "They are on cloud nine."

National holidayWestminster Abbey, where kings are crowned, has close links with the British monarchy. Queen Elizabeth II was married there in 1947, as was her daughter Princess Ann, and son Prince Andrew. It also holds sad memories for William, as the site of Princess Diana's funeral in 1997.

Prior to Monday's announcement, it had been widely speculated that the nuptials would take place at Westminster Abbey. Middleton was photographed leaving the abbey last Wednesday night, after the church closed for a private viewing.

The wedding day will be a national holiday in Britain, known there as a bank holiday, and has been described as a semi-state occasion. It's also the feast day of St. Catherine of Siena, whose name Middleton shares — though that is a coincidence.

"The wedding of Kate and William will be a happy and momentous occasion," said Prime Minister David Cameron on Tuesday. "We want to mark the day as one of national celebration, a public holiday will ensure the most people possible will have a chance to celebrate on the day."

Slideshow: A royal couple’s long courtship (on this page)
At the time of the announcement, Queen Elizabeth was attending the annual meeting of Anglican leaders inside the abbey. The royal family was under increasing pressure to announce the wedding date before the queen leaves on a five-day state visit to the Gulf.

With the date and venue set, the couple — and needless to say the media — will now turn their attention to other wedding details like Middleton's dress, the guest list and the make up of the wedding party.

To help Middleton adjust to her new role as princess, the royal family has turned to the Countess of Wessex, Sophie, who is married to the queen’s youngest son, Prince Edward.

“The palace is very aware that she is going to be taking on the biggest role of her life and they are paving the way for there to be a support network for her,” said royal expert Camilla Tominey to NBC’s TODAY. “The queen is a massive fan of the Countess of Wessex and she’s very much of Kate’s ilk. There is a feeling that Sophie could help guide Kate into the role.”

Excitement in BritainThe upcoming royal wedding has been the story on everyone's lips in the U.K., and indeed around the world. Newspapers have been speculating about the date since the official engagement announcement, with dates in July and August also thought to be strong possibilities.

Middleton met William at the University of St. Andrews in Scotland. They shared a student house in the seaside university town, where William initially studied art history before switching to geography.

Once the couple's relationship became public with a joint photo on a Swiss skiing holiday in 2004, Middleton became a media darling — especially after both graduated, ending a media agreement to leave William alone while he was at university. With her confident good looks and long brown hair, Middleton became one of the most photographed women in Britain.

The brunette fashion buyer was photographed attending public events, going to work, even getting a parking ticket — a level of attention that evoked the romance of William's parents, Charles and Diana.

It has been widely reported that for the last six months, the pair have lived together on the Welsh island of Anglesey, close to the RAF base where the prince is based. William is also a frequent visitor to the Middleton family house in the affluent village of Bucklebury, 50 miles west of London.

Prince William proposed to Middleton during a vacation in Kenya in October. He gave the future princess the engagement ring that belonged to his late mother, Princess Diana.

More than three-quarters of those surveyed for one opinion poll believed the wedding would be good for the monarchy while another suggested most Britons wanted William to be the next king instead of his father Prince Charles.

Whimsical hats

Princess Anne of England matched a fun orange hat to her suit at the Ascot Racecourse in 2009, the same year Kate paired a matching hat with her lavender coat at the wedding of a British aristocrat.
(Samir Hussein/WireImage; Indigo/Getty via InStyle.com)
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Equestrian chic

Princess Charlotte Casiraghi of Monaco looked ready to ride in 2003 at the International Horse Jumping Show. Kate Middleton went for a similar look with tall riding boots and a crisp white skirt in 2007 at the Badminton Horse Trials.

Classic coats

Princess Caroline of Monaco looked chic in a classic trench in London in 1973. The same style still looked fresh on Kate Middleton in 2008 as she watched Prince William receive his military pilot's wings.
(Popperfoto/Getty; Michael Dunlea/AP via InStyle.com)
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Feathered hats

Princess Diana wore a feathered hat for outing in Pembrokeshire in 1981, while Kate Middleton wore an almost-identical one to a wedding in 2006.
(Jayne Fincher/Getty; Tim Graham/Getty via InStyle.com)
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Metallic gowns

Crown Princess Victoria of Sweden wore a beautiful bronze silk gown to a banquet for the Danish Royals in 2007. Kate opted for an elegant chrome-colored gown for the annual Starlight Children's Foundation event in 2009.

Feminine florals

Queen Rania of Jordan chose a delicate floral dress for a Royal Military Academy parade in 2006. In 2007, Kate Middleton wore a similar carefree look on a walk through West London.
(MJ Kim/Getty; Ramey Photo via InStyle.com)
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